Present day shopping often involves the use of carts which allow shoppers to select various merchandise and conveniently transport the merchandise from their respective display locations to a check-out or payment counter. The advent of the shopping cart apparently resulted from increased centralization of merchandise into larger, more diversified retail outlets. For example, neighborhood food markets were supplanted by larger centralized grocery stores which typically were able to offer a larger variety of food items at reduced costs due to volume of sales. Likewise, neighborhood stores, such as general merchandise stores and the like, have been eliminated by competition from large, general merchandise department stores and shopping malls. Recently, a new wave of competition to existing retail outlets has been developed in the form of warehouse-like "mega stores" wherein virtually all of a consumers merchandise needs may be found under a single roof.
The reason that the development and increased use in shopping carts resulted from this competitive structure is that consumers desired to sacrifice the convenience of small local stores for the reduced prices offered by larger, centralized retail outlets. A natural circumstance of this development is that consumers now find themselves more distant from the centralized retail outlet. Accordingly, consumers have changed their shopping pattern from one in which a few items were purchased, almost daily, from local stores to pattern where a consumer purchases an inventory of supplies on a periodic (e.g. weekly or bi-weekly) basis. Since a consumer purchases an inventory of supplies, often at a single store, it has become virtually impossible for the consumer to carry all of the selected goods in his/her arms or in hand-held baskets during the shopping excursion. Therefore, the management of centralized retail outlets have found it necessary and profitable to supply shoppers with transportable shopping carts which can conveniently hold a large volume of goods that are selected during the shopping excursion and which goods may then be transported to a payment counter for a single purchasing transaction.
Shopping carts in common use have some minor differences in appearance and construction, but they are found to have a fairly standard structure. The standard shopping cart includes a large plastic or wire basket which is supported on a wheeled frame typically manufactured from tubular metal elements. More specifically, the wheeled frame usually has a lower, horizontal frame portion which is U-shaped in appearance with forwardly convergent side rails which are joined at the front region by a downwardly turned lip. The side rails supports upright tubular members which, in turn, position the basket in spaced-apart, parallel relation to the horizontal lower framework. A handle is connected to the upper rear portion of the basket, and the basket extends forwardly and converges inwardly to terminate in a nose portion. An auxillary merchandise support, in the form of a wire platform, is often provided on the lower horizontal framework.
When these shopping carts are not in use, store managers find it desirable to store the array of carts in a minimum space; therefore, these shopping carts are constructed so that they may be nested together. Here, adjacent ones of the carts form mated pairs defined by an inner cart and an outer cart. More specifically, when in the nested state, the basket of the inner cart is telescopically received in to the interior of the basket of the outer cart while the lower framework of the inner cart slides interiorly alongside the lower framework of the outer cart. It is for this reason that both the basket and the lower framework of each cart is forwardly convergent from the rear or handle portion. Further, to allow this nesting, the back section of each basket is hinged at an upper portion thereby allowing the back section of the outer basket to be elevated by the nose of the inner basket as it is moved toward the nested state so that the back section rides up and over the basket of the inner cart. Likewise, the auxiliary wire platform is hinged forwardly of the lower horizontal framework so that it may ride up and over both the downwardly turned lip of the lower framework and the auxillary wire platform of the inner cart as the inner cart is advanced into the nested state.
One problem resulting from this standard structure and nesting procedure is widely recognized by both shoppers and merchants, alike. This problem concerns the tendency of a mated pair of shopping carts to bind with one another so that it becomes difficult for a shopper or store employee to separate an outer cart from an inner cart. As disclosed in this application, the binding typically occurs not between the baskets or upright frame pieces, but rather, this binding occurs as a result of longitudinal abrasion between the side rails of the lower horizontal frameworks. Even where the side rails are additionally manufactured as smooth tubular pieces, repetitive frictional contact between the side rails of the inner and outer carts during nesting and unnesting causes a roughing which increasingly deteriorates the sliding surfaces. Also, environmental conditions can deteriorate the contacting side rail surfaces. Eventually, the abrasion and deterioration may become sufficiently severe so that the side rails tend to frictionally lock against one another, i.e., bind together, when the shopping carts are in the nested state. This problem may be further exacerbated where the carts are at a cold temperature when nested but are then moved to a warmer environment, such as the interior of the store since any thermal expansion may act to tighten the frictional fit of a mated pair of carts.
Despite the widespread recognition of this binding problem in an array of nested shopping carts, the present inventor knows of no commercially available solution to this problem either provided as a original piece of manufactured equipment or as a retro-fit device. Accordingly, there has been a long felt need for a solution to this problem. Further, since there are literally millions of shopping carts in use, there is a need for a simple retro-fit device which may be mounted on common shopping carts to help alleviate this problem.